I'm going to try my hand at this, but want to go all grain. The recipe calls for 5lbs light DME and steeping 5lbs of C120 and Special B.

10lbs total of C120 and Special B seems like a shitload of caramelized malts in the mash tun. Throw in the 8.5lbs of 2-row and that is a craptop of grain in the tun.

So my question is how much C120 and Special B to add to the mix and what would be a good mash temp? 155?

OR

Would be I better off mashing the 2-row normally, then at the end of the mash add all the specialty grains and raise the mash temp with heated water to raise it to 170 and offset the water absorption of the newly added grains?